Hardeep Singh Kohli chooses a word and sets off on an exploration into its origins, meeting people for whom it has different associations. He hopes to learn 15 things along the way.
Today's word is 'Hip', which shoots off in various directions from different roots.
Susie Dent is on hand to trace the origins of the different meanings, from the anatomical sense to the essence of 'cool'.
Hardeep tests Amber Butchart on who is 'hip' and who is not, talks to orthopaedic surgeon Adrian O'Gorman about the sharper points of hip replacements, and gets his come-uppance from salsa teacher Douglas Gomes as he tries to make Hardeep's hips move to the Latin-American beat.
And there are shorter excursions into the origins of hip hip hooray and hip hop.
Producer: Richard Bannerman
A Ladbroke production for BBC Radio 4.